Method of making sugar and sugar products

ABSTRACT

Process of making sugar and products containing predominantly sugar wherein sugar syrups are evaporated and then beaten to make a fondant-like material by a process wherein the crystallized product is screened to produce an intermediate, salable, fraction of the desired particle size, a coarse material (scalpings) and a fine material. The fine material is pelletized and combined with the coarse material and passed through a comminutor and the comminuted product is returned to the screening stage. This produces a product having a particle size distribution within a narrow range which is free flowing and in practically 100 percent yield.

United States Patent Schwer et al.

[15] 3,655,442 [451 Apr. 11, 1972 54] METHOD OF MAKING SUGAR AND3,257,236 6/1966 Schwer et a1 ..127/30 x SUGAR PRODUCTS 3,447,962 6/1969Megolden ..l27/63 [72] Inventors: Frederick W. Schwer, Orinda; ChesterE. OTHER PUBLICATIONS Kean Lafayette both of Cahf Agglomeration,Chemical Engineering, pp. 161- 168 (Oct. [73] Assignee: California andHawaiian Sugar Company 1951) [22] Filed: 1969 Primary ExaminerMorris O.Wolk [21] A L N 853,361 Assistant Examiner-Sidney MarantzAttorney-Eckhoff and Hoppe [52] US. Cl. ..127/58, 99/DIG. 4,11227706623, 57 ABSTRACT 51 1111.01. ..c13r 1/02 Process of making sugarand Products containing P 58 Field of Search ..127/29, 30,58,63,69, 62;namly Sugar wherein Sugar y p r evaporated and e 99/DIG 4 beaten to makea fondant-like material by a process wherein the crystallized product isscreened to produce an inter- 6 f mediate, salable, fraction of thedesired particle size, a coarse [5 1 Re erences cued material(scalpings) and a fine material. The fine material is UNITED STATESPATENTS pelletized and combined with the coarse material and passedthrough a comminutor and the comminuted product is 2,098,604 1 1/1937Whymper ..127/30 returned to the Screening Stage This produces a product2,400,292 5/1946 DFiItOH "127/30 ing a particle size distribution withina narrow range which is 2,824,808 2/1958 Glllett et al. .99/DIG. 4 freeflowing and in practically 00 percent yield. 3,194,682 7/1965 Tippens etal. ..l27/30 3,212,908 10/1965 Childs et al. ..127/63 X 3Claims, 1Drawing Figure BEATERS 0R 6 CREAMERS SAW- ROLL AS s E M a LY (OPTIONAL)DRYER lo (OPTIONAL) I6 -I I ROTE SCREEXN I I I8 I FINES I PELLETIZER I IAND COOLER I INTERMEDIATE l SCALPINGS I FRACTION I PRODUCT go/lCOMMINUTOR I4 I I METHOD OF MAKING SUGAR AND SUGAR PRODUCTS SUMMARY OFTHE INVENTION It is known to produce products which are composedessentially of sucrose by evaporating a sugar syrup and then passing thesugar syrup through a beater or creamer whereupon it crystallizes intogranular aggregates of dried fondant. The sugar syrup may be essentiallypure sucrose of it can contain other naturally occuring substances oradditives. Thus the process lends itself for producing products fromwhite sugar of 100 percent purity (on a solids basis) to brown sugarwhich contains as little as 85 percent sugar, the balance beingnaturally occuring substances derived from sugar cane which gives thebrown sugar its characteristic color and taste.

Also in accordance with the present invention, other additives may bepresent such as corn syrup solids and dextrine which can be employed upto the extent of 30 percent. Dextrose can be incorporated in the mixtureup to percent. Other materials can be added such as minerals like sodiumorthophosphate, sodium hydrogen phosphate and sodium dihydrogenphosphate, coloring, vitamins, flavoring or the like.

It is already known that sugar can be made by a process wherein any ofthe liquors and syrups from a sugar refinery as well as other materialsuch as corn syrup solids, dextrine and dextrose are first evaporated toremove most of the water so that a viscous syrup containing 93 percentor more of solids is obtained. This can be done in conventional candycooking equipment either at atmospheric pressure or under vacuum and itmay be either a batch or a continuous process. After the evaporationstep, the concentrated syrup is then transferred to a beating orcreaming apparatus which induces rapid crystallization by agitation.During agitation, sufficient heat of crystallization is released tofurther evaporate the moisture so that a solid, fondantlike productcontaining less than 1 percent water is obtained. Obviously during thisstage it is necessary to remove the water vapor to prevent it fromrecondensing in the sugar.

The most commonly used beating apparatus is a trough equipped with ashaft to which arms have been attached. Stationary fingers attached tothe trough set between the arms make the equipment self-cleaning andimprove the agitation. It is also possible to use more than one shaftwith the arms on adjacent shafts passing between each other.

This produces a sugar product which contains less than 1 percent waterwhich is essentially a mass of fondant-like agglomerates. This has arather broad particle size distribution and is unsuited for sale. Inorder to be a useful article of commerce, a more uniform particle sizedistribution must be achieved in order to ensure reasonable freedom fromcaking tendencies and to offer the user grain sizes which function bestin his product. The more uniform the particle size, the fewer the pointsof contact which are available to particles to cement together whenexposed to variable atmospheric conditions. Further, consumers expect auniform product and do not look with favor upon a product having a broadrange of particle sizes, particularly one containing a quantity offines.

Such a product could be obtained merely by screening the fondantmaterial but this would be wasteful since the fines and large particleswould not fall within the salable range.

The present invention provides an effective way of utilizingsubstantially 100 percent of the sugar and producing a product ofuniform particle size which is essentially nonhygroscopic.

This is accomplished by providing a screen wherein the product from thebeaters or creamers is divided into three fractions. One of these is anintermediate fraction of a desired particle size, the second fraction istoo fine for use and a third fraction is too coarse for use. The finefraction is passed through a pelletizer and cooler and then combinedwith a coarse or scalped fraction. The combined fractions are thenpassed through a comminutor and the comminuted product is now returnedto the screening operation. Thus the particles which are too small arepelletized and then ground to a proper size while those which are toolarge are ground to the desired size. Naturally such a grindingoperation will again produce some fines but these will be picked up inthe process and repelletized so that there is no net loss of sugarmaterials.

BRIEF DESCRIPTION OF THE DRAWING The sole FIG. of the drawing is a flowdiagram illustrating the process.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference is made to the flowsheet given in the FIG. In accordance with this drawing, a liquor feed2, as is hereinafter described, is passed to cookers 4, where it isevaporated down to at least 93 percent solids. It is then passed to abeater or creamer 6, as hereinafter described. Optionally the materialfrom the beaters can be passed through saw-roll assembly 8, to reduceparticle size and to a dryer 10, although these steps are not essentialto the process. The material is then fed into a screen 12, where theproduct is divided into three fractions. The fraction of the propersize, i.e. an intermediate fraction passes into the product receiver 14.

Particular reference is made to that part of the FIG. enclosed in thedashed line 16. It can be seen that the oversize and undersize from thescreening operation both are continuously processed to produce a productin the desired particle range. The scalpings (oversize) are sentdirectly to the comminuting mill 20 where they are broken down intofiner particles yielding about 50 percent in the desired range and theremainder requiring rescreening and re-processing.

The fines are built up into larger particles in pelletizer 18 by beingforced through a rotating die under extreme pressure to form pelletswhich in this case are small cylinders about onefourth of an inch indiameter and about one-fourth to threeeighth inches long. The pelletsare plastic when they emerge and must be allowed to cool whereupon theybecome quite brittle and are easily comminuted into smaller but usableparticles which become part of the product One suitable machine used forpelletizing the fines is of the type manufactured by the CaliforniaPellet Mill Company for the purpose of pelletizing feed for animals aswell as other materials. The operation consists of uniformly passing thefeed material into the interior of a cylindrical die whose walls havebeen perforated radially with holes equal to the size of pellet desired.Pressure rollers inside the dire force the feed mix through the dieholes under extreme pressure. As mentioned above, considerable heatdevelops due to the compression causing the pellet to be plastic inconsistency when it emerges from the die. Adjustable knives or wires arelocated next to the rotating die to slice off the pellets to the desiredlength.

The pellets are then cooled, preferably by passing them through acommercial cooling device such as that manufactured by California PelletMill Company. Countercurrent air effects the cooling. Pellets emergefrom the cooler and are cycled back to the screen for routing to thecomminuting mill along with the scalpings. They may also be sentdirectly to the mill if desired.

In addition to sugar products normally found in a sugar refinery,particularly a cane sugar refinery, other additives such as corn syrupsolids and dextrins may be incorporated in the feed stock for conversionto solid granular products. A second approach to incorporating additivesis to introduce them after cooking just ahead of the heaters. This isparticularly useful where the additives might be heat sensitive or reactwith the sugar carrier if left too long at high temperatures. This wouldalso apply to flavors and colors. The following non-limiting examplesillustrate preferred methods of carrying out the inventions.

EXAMPLE I 1,000 gallons of a liquor having the composition set forthbelow was cooked at atmospheric pressure to a temperature of 280-290 F.(l38-l43 C.) by passing through a continuous candy cooker.

Composition of Liquor Sucrose 68.5 Invert Sugar 4.5 Water 24.0 Ash 2.0Non-ascertained 1.0 Solids Content 76.0

The liquor was thereby concentrated by this operation to a solidscontent of 93-96 percent. It was introduced into a precreaming deviceconsisting of a horizontal trough equipped with rotating arms disposedwithin it on a shaft which served to induce crystallization because ofthe agitation and cooling occurring. Once started either by seeding ormechanical agitation crystallization occurred spontaneously andcontinuously in this device. Heat was given off by the act ofcrystallization which resulted in considerable water vapor beingreleased. The latter was vented through a duct under suction.

The still soft fondant-like mass was transferred to a second creamingdevice of the same general design and function as the one justdescribed. Here the beating continued, resulting in particles beingdeveloped and further liberation and dissipation of water. The productapproached 1 percent in water content at this point and consisted oflarge agglomerates of sugar particles ranging up to three-fourth of aninch in diameter.

This material was then run between two smooth rollers whose surfaces arecontinuously cleaned by a third saw tooth roller mounted beneath it. Thelarge agglomerates are thus broken down into smaller particles dependingon the spacing between the rollers. However, the product was notsufiiciently uniform at this point to be considered finished. The rangeof particle sizes was too large varying from about 100 mesh to 4 mesh insize. Further sizing was required.

An optional step following the saw rollers was a drying operation whichtended to remove additional moisture from the particles.

The material was then passed through a conventional screen, in this casea Rotex, having a US. 12 mesh screen on its upper deck and a US. 40 meshscreen in the lower deck. Other mesh sizes may also be used such as US.6, 8, l0, l4 and for the coarse screen and 35,50 and 70 for the finescreens as may be desired. Three fractions were thus obtained (1) theplus 12 fraction was considered too coarse and had to be further brokendown by passing through a comminuting mill, (2) the l2 40 fraction whichwas the product and (3) the -40 fraction which had to be built up intolarger particles or pellets which were then in turn comminuted as in (lAfter screening, the coarse fraction (scalpings) was comminuted in amill. Suitable mills are typified by those known commercially as theFitzmill, Urschel Commitrol, and Entoleter. All are well known to thoseskilled in the art. Their function was to break down a particle intosmaller pieces with a minimum production of powder or dust.

The 40 fraction was a mixture of fine granular material and powder whichwas then fed into a pelletizing mill of the same type as that used forpelletizing animal feed. Pellets roughly cylindrical in shape(one-fourth inch diam. X onefourth inch long) were produced whichinitially were plastic due to the high temperature developed by thecompression. After passing through a cooler (pellets are cooled by astream of ambient air), the pellets became brittle and were thencomminuted in the same mill as used on the scalpings.

Conversion of the scalpings and fines into usable material representedby the mid fraction from the screen was accomplished by these twofunctions of pelletizing and comminuting.

The following table gives representative screen tests of materialsprocessed according to the above examples.

SCREEN TESTS OF PURITY (SQLIDS BASIS) MATERIAL PROCESSED AS INDICATEDComminuted material Scalptngs Urschel Mill Fitzmill Enmleter U.S. SieveNo.:

Pellets Urschel Mill Fltzmill Entoleter 76. 0 5. 0 6 2. 2 8. 5 11. 4 7.1 11. a 5. 4 24. 4 31. l 10. 9 3. 3 14. 2 17. 7 12. 4 2. 0 10. 5 11. 6l2. 2 l. 2 9. 2 9. 6 9. 4 4. 6 25. 3 22. 3 41. 3

EXAMPLE II The same quantities, conditions, and operations were followedas described in Example 1, with the exception that the composition ofthe starting liquor was as indicated:

Sucrose W ater EXAMPLE Ill The same as Example I with the exceptionsthat solutions containing sugar, dextrines and water as indicated in thefollowing table were substituted and the temperatures reached in cookingwere as shown:

Case 1 Case ll Sugar to 85 purity) 49.0 59.5 Dextrines 2i .0 10.5

Water 30.0 30.0 Temp. of cook 260*F. 285F.

EXAMPLE IV The same as Example I with the exception that sugar, dextrosehydrate and water were substituted as the starting material in thefollowing proportions:

Sugar 59.5 Dextrose Hydrate I05 Water 30.0

Temperature 328F.

EXAMPLE V The same as Example I with substituted exception that sugar,corn syrup solids, and water were subsitutied in the followingproportions:

Case Case ll Sugar 49.0 49.0 Corn Syrup Solids 21.0 210 (DE of cornsyrup) Water 30.0 30.0

Temp. of Cook 285F. 285F.

EXAMPLE VI 1. in the making of a sugar material wherein a predominantlysugar syrup is concentrated by heating and crystallized by agitation toproduce a crystallized sugar containing about 1 percent moisture, theimprovement comprising the steps of:

The same as Example I with the exception that sugar, mineral phosphates,and water were substituted in the followmg Proportions: 5 a. screeningthe thus crystallized sugar material to produce three fractions namely,fines, scalpings and an inter- Cm Case case mediate fraction,

b. pelletizing solely the tines, the pelletizing being done Identity ofSodium Sodium Sodium solely by forcing the substantially dry sugar massthrough Pmspha" d'hydmgm 10 a die under extreme pressure whereby thesugar becomes orthoorthophosphate phosphate lastic phosphate p (NEHZPOJ)(Nagflpod (Named c. cooling the thus pelletized material whereupon itSugar 6011 60.0 60.0 becomes brittle, Phosphate 100 d. combining thepelletized fines and the scalpings, 22; of Cook 22;; 22;; 32;; e.comminuting the mixture thus produced, pressure f. returning thecommlnuted material to stop (a), and

g. recovering the intermedlate fraction as product.

Weclaim:

